I know you can “cross link” bp’s so that they read from one another, not sure how though.
An alternative is to make a new dmg type and set the torpor to a reasonable value then you can adjust it via the damage amount of the projectile using .ini like so:
That’s one of the “stun” types I did for Stark Wars. I think I set the torpor in the dmg type to 50 so by default at 10 dmg it gives 500 torpor per shot. And that’s the low one lol 